As far as the design of your web site is considered, you have to put up a really simple and useful layout. People will visit your classified web site for one purpose, to read and respond to ads. Stay away from fancy and heavy graphics. Make sure you include interactive map integrations so people can see where the listing is located. Allow the ad posters to customize as much detail as they can and upload several photos for their listings. Photos get a lot of attention so this is a must. Have some kind of a relation system to show visitors related ads that are similar to ones they are looking for. Again, having one of the classified ad softwares is going to be easier, as most of them come with all these features you can use.
Once your classified web site gets moving, try to advertise it. Start locally and small, put up stickers on school boards and public places. Usage of newspapers, direct mail and hand flyers are also effective ways to get your word out in an affordable way. Your best bet is to start locally and on specific subjects. As you get more visitors and get more postings, you can expand to multiple categories and different cities.
Classified ad websites are really important for the economy. Nowadays most consumers use these web sites to find goods and services. As the number of people using classified ads increase, there will be need for more productive and user oriented web sites catered to specific niches. If you are planning on launching one, now might be a good time, Start now with PHPClassifiedScript.net